Previously, a series of closely related aminobenzophenones (e.g. 4-(2-amino-4-nitrophenylamino)benzophenone) have been described (Hussein, F. A. et al, Iraqi J. Sci., 22, 54–66 (1981). However, there is no description of their uses. WO 98/32730, WO 01/05744, WO 01/05746, WO01/05749, WO 01/05751, WO 01/05745 and WO 01/42189 disclose aminobenzophenone inhibitors of interleukin 1β (IL-1β) and tumour necrosis factor α (TNF-α) secretion in vitro, said compounds being potentially useful for treatment of inflammatory diseases in which the production of cytokines is involved in the pathogenesis, e.g. asthma, rheumatoid arthritis, psoriasis, contact dermatitis and atopic dermatitis.
Furthermore, the compounds of the above mentioned patent applications were tested in vivo for anti-inflammatory properties in the 12-O-tetradecanoylphorbol-13-acetate (TPA) induced murine chronic skin inflammation model, (De Young, L. M. et al., Agents Actions, 26, 335–341 (1989); Carlson, R. P. et al., Agents Actions, 17, 197–204 (1985); Alford, J. G. et al., Agents Action, 37, (1992);                Stanley, P. L. et al., Skin Pharmacol, 4, 262–271 (1991). In this chronic skin inflammation model the compounds had a potency similar to the reference compound hydrocortisone.        
The preparation of structurally related aminobenzophenones useful as dyes for textiles is disclosed in Man-Made Text. India (1987), 30(6), 275–6, Man-Made Text. India (1986), 29(5), 224–30, and Man-Made Text. India (1985), 28(11), 425, 427–9, 431; and a structurally related aminobenzophenone is disclosed in JP 81–61259 as a reactant in the preparation of fluoran dye precursors.
The purpose of the present invention is to provide further pharmacologically active benzophenone derivatives with superior physico-chemical properties, in particular with improved bioavailability.